Pneumatic drill.



Patented Apr.: lo, |900.

E. C. MEISSNER.

PNEUMATIC DRILL.

(Application med may 15, 1599.) (No Mudalf.i

we mums versus cn, Pnorungo., msmmrnn. b. cw

NITED STATE-s PATENT OFFICE.

EDWARD O. MFISSNER, OF ST. LOUIS, MISSOURI, ASSIGNOR TO THF STANDARDRAILWAY EQUIPMENT COMPANY, OF EAST ST. LOUIS, ILLINOIS;

PN EUMATIC DRILL.

srEcirIcAtrIoN forming part of Letters Patent Noem-155, dated April 1o,ieoo,

A l Application led May 15,1899.

serai no. tracas. (No moana T0 all whom t 11m/y concern:

Beit known that I, EDWARD C. MEIssNER,

a citizen of the United States, residing at the being had totheaccompanying drawings,`

forming part of this specification, in which- Figure 1 is a longitudinalsectional view through my improved drill. Fig. 2 is a section-al view online 2 2, Fig. 1. Fig. 3 is a bottom plan view showing thethrottle-valve in longitudinal section. Fig. 4 is a detail longitudinalsectional view through the spindle on which the cylinders are mounted.Fig. 5 is a sectional view on line 5 5, Fig. l. Fig. 6 is a sectionalview on line 6 6, Fig. l.

This invention relates `to a new andouseful improvement inpneumaticdrills, the object being to construct a device of the characterdescribed which will be strong, simple in its construction, and cheap tomanufacture. The drill is designed to be run, preferably, by compressedair as its `motive fluid, which air is supplied to the drill through aflexible hose leading from some suitable source of supply.

With these objects in View the invention consists in the construction,arrangement, and combination of the several parts, all as willhereinafter be described,and afterward pointed out in the claims.

In the drawings, @indicates the top plate, and h the bottom plate, of asuitable casing or housing, between which is arranged the body portion cof said housing, to which body portion the top and bottom plates aresecured by means of screws or other fastening devices d. The forward endof casing c is provided with a cored opening,in which isrotatablymounted a shaft e., which I will term the driven shaft. On the lower endof this shaft is arranged a gear-wheel f, said'wheel being provided witha conical inner face against which rest balls g, seated in a race h. Theball-race h is preferably arranged in the bottom plate of the casing,which is suitably formed to receive the same, said bottom plate alsohaving a projecting flange c', surrounding the gear- V wheel f and itsmeshing pinion. The lower end of shaft e has a clutch, socket, or othersuitable' device j mounted upon it for receiving a bit or drill. (Notshown.) The gear 'f is to provide antifriction devices to take up theend'thrust of the shaft c, which, as shown, isshouldered against s aidgear and prevented from independent rotary motion thereonby means of akey, as isusual. The upper end of shaft c is threaded and provided witha washer and j am-n nts for the purpose of preventing forwarddisplacement of said shaft.'

7c indicates a pinion in mesliwith the gear f, said pinion being pinnedto the lower end of a crank-shaft-Z.

m indicates ball-races introduced into the top and bottom plates a andZJ, respectively, said races providing suitable tracks for balls n, thusformingball-bearings for the crankshaft.

Crank-shaft l is shown in the drawings as what is known as a three-throwcrankshaft; but it is obvious that the number of throws thereof will bedetermined by the number of pistons cooperating'therewith. In the.constrnction shown the cranks in shaft Z, being three in number, arearranged at one hundred and twenty degrees relative to each other, andon these cranks are mounted the outer ends of the pistons, which, asshown in Figs. l and 2, consist of a head 0, a shank p, and an eye q,arranged on the outer end of the shank. This eye q receives theball-race r, which in assembling the parts is slipped over thecrank-shaft in the proper position and the eye of the piston introducedthereon, after which said eye and ball-race are drilled, as at s, forthe introduction of the balls t. After the ball-race is full one extraball u is introduced to iill the opening s and a plug o is inserted inthe eye to close. the same and hold said extra ball in position. Asthere are two sets of balls in each ball-race, I prefer to form theopenings s, leading thereinto, in opposite sides of the eye; but' theycan be arranged on the same side, if desired.

The purpose of introducing the eXtra ball u in the opening s after theball-race is filled is to close said opening to the balls in the objectand purpose of the ball-bearing for the IOO race and insure the presenceof the proper number of balls in said race. The eXtra ball u also actsas a key to lock the ball-race against rotary and lateral movement inits eye or the eye on said ball-race, thus dispensing with any othermeans of fastening between these parts.

w indicates the oscillating cylinders, which are formed with eyes orbearings in their rear ends, which hearings are in alinement and strungon a hollow spindle w, suitably se- Acured between the top and bottomplates a and b of the casing.

I will now describe the manner in which motive iiuid is admitted to thedrill and how said drill may be reversed by the proper manipulation ofits throttle-valve.

7 indicates a nipple arranged on the end of a flexible supply-pipe,which nipple is screwed into a sleeve 8, said sleeve being mounted onthe rear ends of a plug 9, through whose forward end the stem on passes.Plug 9 is provided with a flange 10, between which and the sleeve 8 isarranged a rotary element, which for the sake of simplicity in itsmanufacture consists of three pieces, one a sleeve 11, fitting over theplug 9 and provided with a suitable opening, over which is arranged aninclosing sleeve 12, said sleeve 12 carrying in its forward ends ahollow inutile-ring 13, formed with suitable openings leading to theexterior. These sleeves 1l and 12 and the munie-ring are preferablypinned together, so that they will rotate in unison. Sleeve 8 serves tohold the rotary valve in position on the plug and also acts as a handle,which is designed to be grasped by the operator, the rotary valve beingwithin convenient reach of said handle. The air coming from pipe 7passes through sleeve 8 and enters an axial bore 14 in the plug 9, whichaxial bore connects with the cross-bore 15, opening at both sides of theplug. 16 and 17 are parallel bores in the forward end of the plug, whoserear ends open laterally, as shown in Fig. 3, and whose forward endsterminate at the eye of the plug, through which the spindle sc passes.The spindle is formed with parallel bores 18 and 19, which, throughsuitable lateral openings, register with the bores 16 and 17 of theplug.

One side of sleeve 11 is formed with a slot 20, of which the sleeve 12is the outer wall, said slot being of such length as to establishcommunication between the cross-bore 15 and the rear terminus of eitherof the bores 16 or 17, depending upon the position of the rotaryelement. The opposite side of sleeve 11 and also the sleeve 12 arebored, as at 2l, so as to register with either terminus at the rear endsof the bores 16 and 17 and establish communication between either ofsaid bores and the mncle 13. When slot 2O establishes communicationbetween the inlet-port and the bore 16, the opening 2l is incommunication with the bore 17, which latter bore in such position ofthe parts will be the exhaust-port of the engine. When the rotaryelement is turned one-half of a revolution, the opening 21 may be madeto register with the port 16, which will then be the exhaust-port, andthe slot 2O would establish communication between the inlet-port and thebore 17. By adjusting the rotary element on the plug the available areaof the inlet and exhaust ports of the engine may be controlled at thewill of the operator for the purpose of varying the speed of the engine.By turning the rotary element, say, one-quarter of a revolution both theinlet and exhaust ports are closed. In order to arrest the movement ofthe rotary element in either extreme position, I introduce a pin'22 inthe liange 10 of the plug, which fits in a semicircular recess 23. (SeeFig. 5.) The head of each cylinder is provided with a slot 24, which isdesigned to cooperate With slots 25 and 26, leading from the bores 18and 19, respectively.

The operation of the engine is as follows: Assuming thethrottle-valve'to be in the position shown in Fig. 3, the motive fluidwill pass through the throttle-valve and enter the bore 1S. As theposition of the cylinders on the spindle is determined bythe angle ofthe crank to which its piston is connected it follows that at least oneof said cylinders will have its slot or port in registration with one ofthe slots or ports leading from the bore 18, and pressure will therebybe admitted behind the piston to throw said crank above or below theline of axis, so as to rotate the crankshaft in one direction or theother. The crank-shaft causes the other pistons to re- IOO turn, inwhich movement the pressure behind the same is exhausted through theslots 24 and 25, the bore 19, and through the mufle to the exterior.Each piston of course has a dead central position in which the spindleand cylinder-ports are lapped or blinded; but as the crank-shaft movesbeyond said central position at either end of the stroke thecylinder-port registers with the inlet or exhaust port of the spindle,depending upon whether said piston is in or out. At no time, however,are all three cylinders in such position that all of their ports areblinded, at least one of said openings opening to the inlet-bore andanother opening to the exhaust-bore. By reversing the position of thethrottle-valve the direction of rotation of the engine is likewisereversed.

Handle 27 is preferably arranged on the top plate a in line with thedriven spindle e, and a drill or bit being introduced into the chuck onthe lower end of said spindle is held to its work by the operatorgrasping said handle. I/Vhen the drill or bit is properly centered, thethrottle-valve is rotated so as to drive the drill in the properdirection, and should it be desired to reverse the engine to withdrawthe bit, as when boring wood, after the bit is sunk sufficiently deepthe throttlevalve is turned in an opposite direction, as is wellunderstood. When through using the drill, all that is necessary is toturn the throt- IIO tie-valve about one-quarter of a revolution, so asto close both the inlet and exhaust ports and prevent the operation ofthe engine and the consequent loss of motive power.

While I have shown the speed of the drill reduced to a ratio of aboutone to four, yet it is obvious that a greater or less reduction can behad by changing the gearing.

I am aware that many minor changes in the constructions, arrangement,andcombination of several parts of my device can be made and substitutedfor those herein shown and described Without in the least departing fromthe nature and principle of my invention.

I-Iaving thus described my invention, What I claim, and desire to secureby Letters Patent, is y g l. The combination With a casing, of a spindleiixed therein and provided with inlet and exhaust ports,cylindersmounted on said spindle, pistons in said cylinders, a crank-shaft withwhich said pistons engage, a plug mountcd on the end of the spindle andprovided with ports in registration With the inlet and exhaust ports ofsaid spindle, and a rotary valve coperating with said plug to controlthe admission of pressure to, and exhaust from the spindle-ports;substantially as described.

2. The combination with a casing, of a spindle fixed therein andprovided with inlet and `exhaust ports,cylinders mounted on saidspindle, pistons in said cylinders, a crank-shaft with which saidpistons engage, a plug mounted on the end of the spindle and providedwith ports in registration with the inlet and exhaust ports of saidspindle, and a rotary valve mounted on said plug and provided `withcooperating ports to admit and exhaust pressure to or from either ofsaid spindle-ports, and means for limiting the movement of said valve;substantially as described.

3. The combination with a casing, of a spindle fixed therein andprovided With inlet and exhaust ports,cylinders mounted on said spindle,pistons in said cylinders, a crank-shaft with which said pistons engage,a plug mounted on the end of the spindle and provided with ports inregistration with the inlet and exhaust ports of said spindle, and arotary valve mounted on said plug for admitting or exhausting pressureto or from either of said spindle-ports, and a muiiie cooperating withthe exhaust-passage of said valve; substantially as described.

4E. The combination with a casing of a spindle fixed therein andprovided with inlet and exhaust ports, cylinders mounted on saidspindle, pistons in said cylinders, a crankshaft With Which said pistonsengage, a plug mounted on the end of the spindle and provided With portsin registration with the inlet and exhaust ports of said spindle, and arotary valve comprising sleeves l1 and 12, and a muffle 13, which aresecured together and adapted to rotate on said plug for admitting orexhausting pressure to or from either of said spindle-ports;substantially as described.

5. The-combination with a casing, of a spindle lixed therein andprovided With inlet and exhaust ports, cylinders mounted on saidspindle, pistons in said cylinders, a crankshaft With which said pistonsengage, a plug mounted on the end of the spindle and provided With portsin registration With the inlet and exhaust ports of said spindle, arotary valve cooperating with said plug to control the admission ofpressure to, and exhaust from the spindle-ports, and a sleeve 8 securedto the rear end of said plug for holding said valve imposition, and alsoacting as a handle 5 substantially as described.

In testimony whereof I hereunto affix my signature, in the presence oft-Wo Witnesses, this 10th day of May, 1899.

EDWARD C. MEISSNER.

Witnesses:

F. R. CORNWALL, A. S. GRAY.

